Adjustable-stroke compressor



May 20 1924. 1,494,764

' J. M D. WISHART ADJUSTABLE STROKE COMPRESSOR Filed March 22. 1923 amut JZmasMawa/a! %Zsiarf w.

Witness Patented May 20, 1924.

UNITED STATES JAMES McDONALD wIsH'An'r, or FRESNO, CALIFORNIA.

ADJUSTABLE-STROKE COMPRESSOR;

Application filed. March 22, 1323. Serial No. 626,954.

To all whom it may concern:

Be it known that I, J AMEs M. WISHART, a citizen of the United States, residing at Fresno, in the county of Fresno andeState. of California, have invented certain new and useful Improvements in Adjustable- Stroke Compressors; and Ido declareithe following to be a-full, clear, and exact idea.

scription of the invention, such as will ens able others skilled in the art to which it appertains to make and use the'samei' w w My invention relates to improvements in compressors or pumps andthepresent dis-g closure thereof is directed toacompressor designed primarily for use in connection with refrigeratingjsystems, although notrer.

stricted tosuch use. The compressor iszof the two cylinder,-opposed type in which pistons are operated by a common eccentric disposed between the twocylinders, it being the object of the invention to provide a novel form of adjustable connector between the two pistons for transmitting motion. thereto from the eccentric, said connector-being ads justable to permit eccentrics ;of a different sizes to be used, so that the strokes of the pistons may be varied as occasion may de.-

-With the foregoing in view, the invention resides in the novel subject'matter hereinafter described and claimed, ,thedescription being supplemented by the accompanying drawing, in which a plan 'viewhpartly. in horizontal section is shown of a compressor constructed in accordance with the invention.

In the drawing above briefly described, the numerals 1 designatea pair of opposed axially alined cylinders closed at their outer ends by suitable heads 2 and '0pen atithei r inner ends, said heads carrying appropriate inlets 3' and outlets 4:. The cylindersil'may be mounted in any desiredmannen'for' instance ona cast metal frame 5 and when this frame'is used, it carries a pair of bearings 6 in which a shaft 7 is rotatablymOurited, the axis of this shaft being at right anglesIt'o the cylinder'axis. Any suitable means may be employed for rotating the shaft '7gandJl have illustrated a belt wheel 8 forthispurpose. An eccentric 9 is removably carried by the shaft 7 between the two cylinders 1 and in the present showing, this eccentric is provided with a hub 10 receivingthe shaft, a set screw 11 being threadedthrough said hub for securing the eccentricluponthe shaft. In the preferred form of construction, a steel band 12 surrounds the eccentric 9 and if desiredlmay-be detachably secured here o, y means of, ws 0 th fi e 1 Thus, instead of removingthe entire eccencia n tall ng noth r, if th t ek f rompres or sm he cha ge t i iy necessary tore novethe band 1 2 andj substi tute on -hav g ad fleren thick u v is i ablep ston la e n ed int 3' e lend ar g dw j t ble p m qr-li prov ded; between said pistons, said connector having adjustable shoes. 15 for contact with opposite points, on thefeccentric, thepreferred form ofconstruction, connect rab t e l th two pistons, in udew pair of piston rods 16 carryingsaid pistons and extending toward each -other, 1 and a yoke 17 1 c nnec i g s idepist n r de I pr fer to hread, the: rods l 'i-thrqug o ir lengths, to provide the pistons withlthreajd t;

d oc e r ce v ng the Date en e- 9 S P n d and t 'pr vi a d i ton W t s -s rews. 18 ,f r .ho ding the r dsage t rotation-with? e man-to"sn -Pis ol h endsof t eyoli t l a, ed p n ngs 9 A hr gh w ic he o 6 pass Lad-j fist-ablyvandiset screws or the-like 20 may zb'ep ridc t netea ly hold ai ieks and rods ag inst e atireztn n g-r Terrevent; turning of the pisto Q a-l a yoke; 17, as a unit, the-body portion of said yoke, which is parallel, withltthe Piston rods, gage a uita le. g id uhi s-a o r 21-zII1011Iit5Qd in any desiredrnanner.

The; shoes 15 are preferably of cylindrical form and are provided with sockets 22' into which the ,piston' rods 16,.are1adjustably threaded,;:lock nutsor the like; 23- being projusted position. a I L By employing the construction-shown, it will be seen that the distance between the shoes 15 may be varied byloo'sening the lock nuts 23 and turning said shoes to causethern to travel inwardly .or outwardly upon the piston rods 16, thereby; permitting an eccentrio of a different size to'be used, to change the strokes. of the pistons 14:. Also, by looseningthe se't s'crews 20 and turningthe' piston; rods 16 in the ends of -the-yokej17j, the distance between said pistons may be 'vided to normally hold said. shee s in ad'- changedif-desired; 1 a Z From the'above,.it will be seen that a compressor orpump has been jproyided which are med t t r dmay be adjusted to meet a great number of requirements, and as excellent results may be obtained from the details disclosed, they longitudinally extensible and retractable rigid connectorbetween said pistons having means engaging Silld GCCGl'lhl'lO to receive motion thereirom,said means being adjustable upon said connector toward and away from said eccentric independently of the longitudinal adjustment of said connector.

2. The combination with'a pair of opposed cylinders, a driven eccentricbetween them, and pistons in said cylinders; oi a rigid connector between said pistons having shoes for engagement with opposite points of the eccentriqsaid shoes being adjustable longitudinally ofthe common piston axis to permit the substitution of an eccentric of another size' 1 3. The structure as specified in claim 2,

said shoes having'iscrewthreaded mounting means, and means for locking them'after adjustment. l j

, 4. The combination with a pair of 0pposed cylinders, a driven eccentric between them, and pistons 'in said cylinders; of a longitudinally adjustable rigid 7 connector between the two pistons, including shoes for contact with opposite points of the eccentric, said shoes being adjustable longitudinally of the piston axis'topermit the substitution of an'eccentric of a diiierent size.

'5. The combination, with" a pair of opposed cylinders, a driven eccentric between them, and pistons'in said cylinders; of a rigid connector between the two pistons con sisting of a main central section and two end sections connected with the pistons and relatively adjustable with respect to said centralsection, said connector having means engaging the eccentric to receive motion therefrom, said means being adjustable upon said connector toward and away from said eccentric independently of the longitudinal adjustment of said connector.

6. The combination witha pair of opposed cylinders, a driven eccentric between them, and pistons'in said cylinders; of a pair of'threaded piston'rods extending inwardly toward each other from said pistons, and a yoke through the ends of which said piston rods are threaded adjustably, said rods and yoke forming a rigid connector between the two pistons,-said connector being provided with means engaging said eccentric to receive motion therefrom, said means being adjustable upon said connector toward and away from said eccentric inde pendently of the longitudinal adjustment of said connector.

7.. The combination with a pair of opposed cylinders, a driven eccentric between them, and "pistons in said cylinders; of a yoke between the two pistons having openings in its ends alined with the piston axis, pistonrods extending inwardly toward each other from the pistons and passing-adjustably through said openings oi said yoke, said yoke and piston rods forming an adj ustable rigid connector between the two pistons, and means carried by said connector and engaging said eccentric to receive motion therefrom, said means being adjustable upon said connector toward and awayfrom said eccentric independently of the longitudinaladjustment of said connector. v

8. The combination with a pair of opposed cylinders, a driven eccentric between them, and pistons in said cylinders; of a pair of piston rods extending inwardly toward each other from said pistons, a yoke connecting said piston rods with eachother, and shoes longitudinally adjustable upon the inner ends of said piston rods and engaging opposite points of said eccentric, adjustment of said shoes permittin the substitution of an eccentric of a di erent size.

9. The structure as specified in claim 8, said shoes being threaded "upon said piston rods, and means for normally locking said shoes against rotation upon said rods.

10.'The combination with. a pair ofjopposed cylinders, a driven eccentric between them, and pistons in said cylinders; of a pair of piston rods extending inwardly to,-

ward each 'otherfrom said pistons, a yoke extending between the two piston rods and a having openings in its ends in which said rods are adjustablyheld, and a pair of "eccentric engaging shoes having recesses in which the inner ends of said piston rods are adjustably secured, adjustment of said shoes upon said piston rods permitting the substitution of a difierent eccentric.

'11. The combination with a pair of opposed cylinders, a driven eccentric between them, and pistons insaid cylinders; of a pair of threaded piston rods extending inwardly toward each other from said pistons,

said piston rods, and means for locking said 7 shoes and piston rods against relative turning, adjustment of said shoes on said rods 6 permitting the substitution of a different eccentric.

12. Thecombination with a pair of opposed cylinders, a driven eccentric between them, and pistons in said cylinders; of a rigid connector between the two pistons, including a straight portionparallel with but offset laterally from the common piston axis, and a guide relatively stationary with respect to said straight portion of said connector and engaging the same to prevent rotation of said connector and said pistons, said connector having means engaging said eccentric to receive motion therefrom, said means being adjustable upon said connector toward and away from said eccentric independently of the longitudinal adjustment of said connector.

13. The combination with a pair of opposed cylinders, a driveneccentric between them, and pistons in said cylinders; of a rigid connector between the two pistons having adjustable shoesat opposite sides of said eccentric, and a removable band secured around said eccentric and engaging said shoes, adjustment of said shoes along the piston axis and substitution of a band of difierent thickness serving to change the strokes of the pistons.

In testimony whereof I have hereunto af fixed my signature.

JAMES MCDONALD WISHART. 

